The frequency of cases of accelerated silicosis associated with exposure to dust from processing artificial stones is rapidly increasing globally. Artificial stones are increasingly popular materials, commonly used to fabricate kitchen and bathroom worktops. Artificial stones can contain very high levels of crystalline silica, hence cutting and polishing them without adequate exposure controls represents a significant health risk. The aim of this research was to determine any differences in the emission profiles of dust generated from artificial and natural stones when cutting and polishing. For artificial stones containing resins, the nature of the volatile organic compounds (VOCs) emitted during processing was also investigated. A selection of stones (two natural, two artificial containing resin, and one artificial sintered) were cut and polished inside a large dust tunnel to characterize the emissions produced. The inhalable, thoracic, and respirable mass concentrations of emissions were measured gravimetrically and the amount of crystalline silica in different size fractions was determined by X-ray diffraction. Emissions were viewed using scanning electron microscopy and the particle size distribution was measured using a wide range aerosol spectrometer. VOCs emitted when cutting resin-artificial stones were also sampled. The mass of dust emitted when cutting stones was higher than that emitted when polishing. For each process, the mass of dust generated was similar whether the stone was artificial or natural. The percentage of crystalline silica in bulk stone is likely to be a reasonable, or conservative, estimate of that in stone dust generated by cutting or polishing. Larger particles were produced when cutting compared with when polishing. For each process, normalized particle size distributions were similar whether the stone was artificial or natural. VOCs were released when cutting resin-artificial stones. The higher the level of silica in the bulk material, the higher the level of silica in any dust emissions produced when processing the stone. When working with new stones containing higher levels of silica, existing control measures may need to be adapted and improved in order to achieve adequate control.

Face shields (also referred to as visors), goggles and safety glasses have been worn during the COVID-19 pandemic as one measure to control transmission of the virus. However, their effectiveness in controlling facial exposure to cough droplets is not well established and standard tests for evaluating eye protection for this application are limited. A method was developed to evaluate face shields, goggles, and safety glasses as a control measure to protect the wearer against cough droplets. The method uses a semi-quantitative assessment of facial droplet deposition. A cough simulator was developed to generate droplets comparable to those from a human cough. The droplets consisted of a UV fluorescent marker (fluorescein) in water. Fourteen face shields, four pairs of goggles and one pair of safety glasses were evaluated by mounting them on two different sizes of breathing manikin head and challenging them with the simulated cough. The manikin head was positioned in seven orientations relative to the cough simulator to represent various potential occupational exposure scenarios, for example, a nurse standing over a patient. Droplet deposition in the eyes, nose and mouth regions were visualised following three ‘coughs’. Face shields, goggles, and safety glasses reduced, but did not eliminate exposure to the wearer from droplets such as those produced by a human cough. The level of protection differed based on the design of the personal protective equipment and the relative orientation of the wearer to the cough. For example, face shields, and goggles offered the greatest protection when a cough challenge was face on or from above and the least protection when a cough challenge was from below. Face shields were also evaluated as source control to protect others from the wearer. Results suggested that if a coughing person wears a face shield, it can provide some protection from cough droplets to those standing directly in front of the wearer.

Desktop three-dimensional (3D) printers are used in businesses, schools, and colleges, and are generally of an unenclosed design which may give rise to injuries or inhalation exposure to emissions of small particles (<1 µm) and volatile organic compounds (VOCs). The aim of this work was to explore the health risks related to the use of desktop 3D printers in workplaces in the United Kingdom. A digital survey on the use of desktop 3D printers was completed voluntarily and anonymously between February and June 2023, receiving 146 responses. The most common technology and material used for printing were “filament deposition” and “polylactic acid,” respectively. The median number of printers an organisation had in use in one room was 2. A median of 10 people could be in the room during printer operation. A range of finishing techniques were reportedly applied to the printed object including the use of hand tools and solvents. General room ventilation was the most common exposure control measure stated. Measurements of airborne particles and VOCs were taken at 2 sites: a university and an engineering workshop. Airborne particle number concentrations (<1 µm) did not significantly increase above background levels when the printers were operating at either site. At the university, where there was the largest number of printers in operation, some VOCs could be attributed to the printing process; however, concentrations remained low. Evidence of associated respiratory symptoms was gathered by asking volunteers at the 2 sites visited to complete a questionnaire. Seventeen volunteers across the 2 sites completed the survey. None stated that they had ever experienced acute symptoms from working with 3D printers. However, they did report symptoms which included tiredness, dry/cracked skin, headache, itchy/runny nose, and a cough, with some stating that these improved on their days off. Overall, limited evidence from published literature and this study suggests that exposure to desktop 3D printing emissions could be associated with short-term respiratory health symptoms. However, static measurements in 2 workplaces where multiple desktop 3D printers were in use did not show airborne particle number concentrations in the room rising above background levels and concentrations of measured VOCs were all low. These findings may be due to effective ventilation and other control measures which over half of the workplaces surveyed stated that they had in place.

Background: A cough is known to transmit an aerosol cloud up to 2 m. During the COVID-19 pandemic of 2020 the United Kingdom’s National Health Service (NHS), other UK government agencies and the World Health Organization (WHO) advised people to cough into their elbows. It was thought that this would reduce viral spread and protect the public. However, there is limited peer reviewed evidence to support this. Objectives: To determine if cough related interventions reduce environmental contamination, protecting members of the public from infection. Methods: Scientists and engineers at the Health and Safety Executive (HSE) laboratory used a human cough simulator that provided a standardised cough challenge using a solution of simulated saliva and a SARS-CoV-2 surrogate virus; Phi6. Pseudomonas syringae settle plates were used to detect viable Phi6 virus following a simulated cough into a 4 × 4 m test chamber. The unimpeded pattern of contamination was compared to that when a hand or elbow was placed over the mouth during the cough. High speed back-lit video was also taken to visualise the aerosol dispersion. Results and Discussion: Viable virus spread up to 2 m from the origin of the cough outwards in a cloud. Recommended interventions, such as putting a hand or elbow in front of the mouth changed the pattern of cough aerosol dispersion. A hand deflected the cough to the side, protecting those in front from exposure, however it did not prevent environmental contamination. It also allowed for viral transfer from the hand to surfaces such as door handles. A balled fist in front of the mouth did not deflect the cough. Putting an elbow in front of the mouth deflected the aerosol cloud to above and below the elbow, but would not have protected any individuals standing in front. However, if the person coughed into a sleeved elbow more of the aerosol seemed to be absorbed. Coughing into a bare elbow still allowed for transfer to the environment if people touched the inside of their elbow soon after coughing. Conclusions: Interventions can change the environmental contamination pattern resulting from a human cough but may not reduce it greatly.

Exposure to flour dust remains one of the leading causes of occupational asthma in Great Britain (GB). The average annual incidence rate per 100,000 bakers and flour confectioners in GB was 47.8 for the 3 yr period 2017 to 2019 compared with 0.53 for all occupations. There are many processes in commercial bakeries that can cause exposure to flour dust. Exposures are typically controlled by using local exhaust ventilation or respiratory protective equipment. The aim of this study was to evaluate the potential to reduce exposure to inhalable flour dust in commercial bakeries by modification of the process by use of a conical sieve in place of a round sieve; and substitution of traditional wheat flour (TWF) with ‘low dust’ flours LD1 and LD2 for dusting surfaces. Two simulated commercial bakery tasks were performed in a laboratory whilst dust exposures were measured in the breathing zone of the operator using an Institute of Occupational Medicine (IOM) sampler, button sampler and a real-time direct reading monitor. Analysis of variance tests were used to assess whether differences in mean exposures were statistically significant with the different control approaches. A qualitative visual exposure assessment was also undertaken using Tyndall illumination. Substituting TWF with LD1 and LD2 reduced exposure to inhalable flour dust by 86% and 53% respectively when sieving and by 78% and 67% respectively when filling a hopper. There was no statistically significant difference between dust emissions for all 3 flours when using the conical sieve instead of the round sieve for flour dusting tasks. This laboratory study has shown that substituting TWF with low-dust flour may reduce inhalable dust exposures when dusting surfaces in bakeries.

Face shields (also referred to as visors), goggles and safety glasses have been worn during the COVID-19 pandemic as one measure to control transmission of the virus. However, their effectiveness in controlling facial exposure to cough droplets is not well established and standard tests for evaluating eye protection for this application are limited. A method was developed to evaluate face shields, goggles and safety glasses as a control measure to protect the wearer against cough droplets. The method uses a semi-quantitative assessment of facial droplet deposition. A cough simulator was developed to generate droplets comparable to those from a human cough. The droplets consisted of a UV fluorescent marker (fluorescein) in water. Fourteen face shields, four pairs of goggles and one pair of safety glasses were evaluated by mounting them on two different sizes of breathing manikin head and challenging them with the simulated cough. The manikin head was positioned in seven orientations relative to the cough simulator to represent various potential occupational exposure scenarios, for example, a nurse standing over a patient. Droplet deposition in the eyes, nose and mouth regions were visualised following three ‘coughs’. Face shields, goggles and safety glasses reduced, but did not eliminate exposure to the wearer from droplets such as those produced by a human cough. The level of protection differed based on the design of the personal protective equipment and the relative orientation of the wearer to the cough. For example, face shields and goggles offered the greatest protection when a cough challenge was face on or from above and the least protection when a cough challenge was from below. Face shields were also evaluated as source control to protect others from the wearer. Results suggested that if a coughing person wears a face shield, it can provide some protection from cough droplets to those standing directly in front of the wearer.